Respiratory distress following major trauma. Predictive value of blood coagulation tests.

We have evaluated the use of laboratory parameters to predict the risk of adult respiratory distress syndrome (ARDS) at an early stage after major trauma. Patients with lung contusion were excluded. Five of 29 patients fulfilled our criteria of ARDS, i.e. PaO2/FiO2 less than or equal to 38. They showed lower platelet counts and antiplasmin as well as a tendency to lower antithrombin III, fibrinogen, and plasminogen. These changes indicated activation of the coagulation and fibrinolytic systems by trauma. The most sensitive indicator of ARDS seemed to be the platelet count, although it was also related to blood loss and amount of blood transfused. Hence the platelet count should be considered in relation to blood replacement in the patient with major trauma. Tentative laboratory values are suggested to indicate risk levels of developing ARDS.